/***
 * ASM: a very small and fast Java bytecode manipulation framework Copyright (c) 2000-2011 INRIA,
 * France Telecom All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without modification, are permitted
 * provided that the following conditions are met: 1. Redistributions of source code must retain the
 * above copyright notice, this list of conditions and the following disclaimer. 2. Redistributions
 * in binary form must reproduce the above copyright notice, this list of conditions and the
 * following disclaimer in the documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the copyright holders nor the names of its contributors may be used to
 * endorse or promote products derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
 * FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY
 * WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
package com.googlecode.aviator.asm;

/**
 * An {@link FieldVisitor} that generates Java fields in bytecode form.
 *
 * @author Eric Bruneton
 */
final class FieldWriter extends FieldVisitor {

  /**
   * The class writer to which this field must be added.
   */
  private final ClassWriter cw;

  /**
   * Access flags of this field.
   */
  private final int access;

  /**
   * The index of the constant pool item that contains the name of this method.
   */
  private final int name;

  /**
   * The index of the constant pool item that contains the descriptor of this field.
   */
  private final int desc;

  /**
   * The index of the constant pool item that contains the signature of this field.
   */
  private int signature;

  /**
   * The index of the constant pool item that contains the constant value of this field.
   */
  private int value;

  /**
   * The runtime visible annotations of this field. May be <tt>null</tt>.
   */
  private AnnotationWriter anns;

  /**
   * The runtime invisible annotations of this field. May be <tt>null</tt>.
   */
  private AnnotationWriter ianns;

  /**
   * The non standard attributes of this field. May be <tt>null</tt>.
   */
  private Attribute attrs;

  // ------------------------------------------------------------------------
  // Constructor
  // ------------------------------------------------------------------------

  /**
   * Constructs a new {@link FieldWriter}.
   *
   * @param cw the class writer to which this field must be added.
   * @param access the field's access flags (see {@link Opcodes}).
   * @param name the field's name.
   * @param desc the field's descriptor (see {@link Type}).
   * @param signature the field's signature. May be <tt>null</tt>.
   * @param value the field's constant value. May be <tt>null</tt>.
   */
  FieldWriter(final ClassWriter cw, final int access, final String name, final String desc,
      final String signature, final Object value) {
    super(Opcodes.ASM4);
    if (cw.firstField == null) {
      cw.firstField = this;
    } else {
      cw.lastField.fv = this;
    }
    cw.lastField = this;
    this.cw = cw;
    this.access = access;
    this.name = cw.newUTF8(name);
    this.desc = cw.newUTF8(desc);
    if (ClassReader.SIGNATURES && signature != null) {
      this.signature = cw.newUTF8(signature);
    }
    if (value != null) {
      this.value = cw.newConstItem(value).index;
    }
  }

  // ------------------------------------------------------------------------
  // Implementation of the FieldVisitor abstract class
  // ------------------------------------------------------------------------

  @Override
  public AnnotationVisitor visitAnnotation(final String desc, final boolean visible) {
    if (!ClassReader.ANNOTATIONS) {
      return null;
    }
    ByteVector bv = new ByteVector();
    // write type, and reserve space for values count
    bv.putShort(cw.newUTF8(desc)).putShort(0);
    AnnotationWriter aw = new AnnotationWriter(cw, true, bv, bv, 2);
    if (visible) {
      aw.next = anns;
      anns = aw;
    } else {
      aw.next = ianns;
      ianns = aw;
    }
    return aw;
  }

  @Override
  public void visitAttribute(final Attribute attr) {
    attr.next = attrs;
    attrs = attr;
  }

  @Override
  public void visitEnd() {}

  // ------------------------------------------------------------------------
  // Utility methods
  // ------------------------------------------------------------------------

  /**
   * Returns the size of this field.
   *
   * @return the size of this field.
   */
  int getSize() {
    int size = 8;
    if (value != 0) {
      cw.newUTF8("ConstantValue");
      size += 8;
    }
    if ((access & Opcodes.ACC_SYNTHETIC) != 0) {
      if ((cw.version & 0xFFFF) < Opcodes.V1_5
          || (access & ClassWriter.ACC_SYNTHETIC_ATTRIBUTE) != 0) {
        cw.newUTF8("Synthetic");
        size += 6;
      }
    }
    if ((access & Opcodes.ACC_DEPRECATED) != 0) {
      cw.newUTF8("Deprecated");
      size += 6;
    }
    if (ClassReader.SIGNATURES && signature != 0) {
      cw.newUTF8("Signature");
      size += 8;
    }
    if (ClassReader.ANNOTATIONS && anns != null) {
      cw.newUTF8("RuntimeVisibleAnnotations");
      size += 8 + anns.getSize();
    }
    if (ClassReader.ANNOTATIONS && ianns != null) {
      cw.newUTF8("RuntimeInvisibleAnnotations");
      size += 8 + ianns.getSize();
    }
    if (attrs != null) {
      size += attrs.getSize(cw, null, 0, -1, -1);
    }
    return size;
  }

  /**
   * Puts the content of this field into the given byte vector.
   *
   * @param out where the content of this field must be put.
   */
  void put(final ByteVector out) {
    final int FACTOR = ClassWriter.TO_ACC_SYNTHETIC;
    int mask = Opcodes.ACC_DEPRECATED | ClassWriter.ACC_SYNTHETIC_ATTRIBUTE
        | ((access & ClassWriter.ACC_SYNTHETIC_ATTRIBUTE) / FACTOR);
    out.putShort(access & ~mask).putShort(name).putShort(desc);
    int attributeCount = 0;
    if (value != 0) {
      ++attributeCount;
    }
    if ((access & Opcodes.ACC_SYNTHETIC) != 0) {
      if ((cw.version & 0xFFFF) < Opcodes.V1_5
          || (access & ClassWriter.ACC_SYNTHETIC_ATTRIBUTE) != 0) {
        ++attributeCount;
      }
    }
    if ((access & Opcodes.ACC_DEPRECATED) != 0) {
      ++attributeCount;
    }
    if (ClassReader.SIGNATURES && signature != 0) {
      ++attributeCount;
    }
    if (ClassReader.ANNOTATIONS && anns != null) {
      ++attributeCount;
    }
    if (ClassReader.ANNOTATIONS && ianns != null) {
      ++attributeCount;
    }
    if (attrs != null) {
      attributeCount += attrs.getCount();
    }
    out.putShort(attributeCount);
    if (value != 0) {
      out.putShort(cw.newUTF8("ConstantValue"));
      out.putInt(2).putShort(value);
    }
    if ((access & Opcodes.ACC_SYNTHETIC) != 0) {
      if ((cw.version & 0xFFFF) < Opcodes.V1_5
          || (access & ClassWriter.ACC_SYNTHETIC_ATTRIBUTE) != 0) {
        out.putShort(cw.newUTF8("Synthetic")).putInt(0);
      }
    }
    if ((access & Opcodes.ACC_DEPRECATED) != 0) {
      out.putShort(cw.newUTF8("Deprecated")).putInt(0);
    }
    if (ClassReader.SIGNATURES && signature != 0) {
      out.putShort(cw.newUTF8("Signature"));
      out.putInt(2).putShort(signature);
    }
    if (ClassReader.ANNOTATIONS && anns != null) {
      out.putShort(cw.newUTF8("RuntimeVisibleAnnotations"));
      anns.put(out);
    }
    if (ClassReader.ANNOTATIONS && ianns != null) {
      out.putShort(cw.newUTF8("RuntimeInvisibleAnnotations"));
      ianns.put(out);
    }
    if (attrs != null) {
      attrs.put(cw, null, 0, -1, -1, out);
    }
  }
}
